<?php
/* vim: set expandtab sw=4 ts=4 sts=4: */
/**
 * Output buffer functions for phpMyAdmin
 *
 * Copyright 2001 Jeremy Brand <jeremy@nirvani.net>
 * http://www.jeremybrand.com/Jeremy/Brand/Jeremy_Brand.html
 *
 * Check for all the needed functions for output buffering
 * Make some wrappers for the top and bottoms of our files.
 *
 * @version $Id: ob.lib.php 10892 2007-11-01 20:48:43Z lem9 $
 */

/**
 * This function be used eventually to support more modes.  It is needed
 * because both header and footer functions must know what each other is
 * doing.
 *
 * @uses	$cfg['OBGzip']
 * @uses	function_exists()
 * @uses	ini_get()
 * @uses	ob_get_level()
 * @staticvar integer remember last calculated value
 * @return  integer  the output buffer mode
 */
function PMA_outBufferModeGet()
{
	static $mode = null;

	if (null !== $mode) {
		return $mode;
	}

	$mode = 0;

	if ($GLOBALS['cfg']['OBGzip'] && function_exists('ob_start')) {
		if (ini_get('output_handler') == 'ob_gzhandler') {
			// If a user sets the output_handler in php.ini to ob_gzhandler, then
			// any right frame file in phpMyAdmin will not be handled properly by
			// the browser. My fix was to check the ini file within the
			// PMA_outBufferModeGet() function.
			//
			// (Patch by Garth Gillespie, modified by Marc Delisle)
			$mode = 0;
		} elseif (function_exists('ob_get_level') && ob_get_level() > 0) {
			// If output buffering is enabled in php.ini it's not possible to
			// add the ob_gzhandler without a warning message from php 4.3.0.
			// Being better safe than sorry, check for any existing output handler
			// instead of just checking the 'output_buffering' setting.
			$mode = 0;
		} else {
			$mode = 1;
		}
	}

	// Zero (0) is no mode or in other words output buffering is OFF.
	// Follow 2^0, 2^1, 2^2, 2^3 type values for the modes.
	// Usefull if we ever decide to combine modes.  Then a bitmask field of
	// the sum of all modes will be the natural choice.

	return $mode;
} // end of the 'PMA_outBufferModeGet()' function


/**
 * This function will need to run at the top of all pages if output
 * output buffering is turned on.  It also needs to be passed $mode from
 * the PMA_outBufferModeGet() function or it will be useless.
 *
 * @uses	PMA_outBufferModeGet()
 * @uses	PMA_outBufferPost() to register it as shutdown function
 * @uses	ob_start()
 * @uses	header() to send X-ob_mode:
 * @uses	register_shutdown_function() to register PMA_outBufferPost()
 */
function PMA_outBufferPre()
{
	if ($mode = PMA_outBufferModeGet()) {
		ob_start('ob_gzhandler');
	}

	header('X-ob_mode: ' . $mode);

	register_shutdown_function('PMA_outBufferPost');
} // end of the 'PMA_outBufferPre()' function


/**
 * This function will need to run at the bottom of all pages if output
 * buffering is turned on.  It also needs to be passed $mode from the
 * PMA_outBufferModeGet() function or it will be useless.
 *
 * @uses	PMA_outBufferModeGet()
 * @uses	ob_flush()
 * @uses	flush()
 */
function PMA_outBufferPost()
{
	if (ob_get_status() && PMA_outBufferModeGet()) {
		ob_flush();
	} else {
		flush();
	}
} // end of the 'PMA_outBufferPost()' function

?>
